Sintering apparatus



y 9 194s.- L. GELBMAN Y 2 40 ,4

SINTERING APPARATUS Filed Feb. 9, 1945 4 Sheets-Sheet 1 IN V EN TOR.

' Lou/s gem/MW BY FITTORA/EX y L. GEL BMAN SiNTERING APPARATUS Filed Feb. 9, 1945 4 Sheets-Sheet 2 July 9, 1946. L. GELBMAN SINTERING APPARATUS Filed Feb. 9, 1945 4 Sheets-Sheet 5 INVENTOR. Lou/s LBM4N BY 3 I July 9,. 1946. GELBMAN SIN'I'ERING APPARATUS Filed Feb. 9, 1945 4 Sheets-Sheet 4 INVENTOR. Lou/5 ELBN/IN BY ,4TTDRA/5X Patented July 9, 146

' UNITED snares 18 Elaims. ll

This invention relates to new and useful improvements in a sintering apparatus.

More particularly, the invention proposes an improved sintering apparatus which works continuously It is proposed that the ingredients to be sintered be fed to the apparatus at one point and that the finished sintered material be discharged at another point. It is proposed to so arrange the apparatus that the operation is continuous without any interruption. As long as sintering material is fed to the machine the sintered material will be delivered. This new and improved sinterlng apparatus is a great improvement over prior devices in which the operation is not continuous. In prior devices it is customary to provide, cars or other reciprocae tive travelling sinter supply mechanism to feed the sinter furnace portion of the device. With this arrangement the apparatus is not continuous but is being interrupted.

More particularly, the new and improved sintering' apparatus is characterized by an annular-like suction box for. connection with a suction fan for providing the air draft needed for sintering. It is proposed to arrange the an nular-like furnace unit rotatively upon said 2 unit may continue to rotate without inten-option during the ignition period.

Still further the invention proposes the construction of a sintering apparatus as briefly described which will be emcient in operation,

exceptionally reliable, and which may be manufactored and sold at a reasonable cost.

For further comprehension of the invention, and of the objects and advantages thereof, ref erence will be had to the following description and accompanying drawings, and to the ap-' pended claims in which the various novel features of the invention are more particularly set forth.

In the accompanying drawings forming a material part of this disclosure:

Fig. 1 is a planview of a sintering apparatus,

constructed in accordance with this invention.

Fig. 2 is a fragmentary developed vertical sectional view taken on the line 2-42 of Fig. l, but illustrated provided with sintering material.

Fig. ii is a fragmentary enlarged transverse lv ertigcal sectional view taken on the line 3-3 of g- Fig. 4 is a fragmentary enlarged horizontal sectional view taken on the line 4-6 of Fig. 2.

suction box. It is proposed that said furnace unit be provided with a plurality of'radially disposed furnace pan sections. Means for filling said pan sections with material to be sintered, is arranged to fill each pan section as it moves past one point of said suction box. Igniting means is provided for igniting the material in each pan section immediately forwards of the filling position. It is proposed to so design the apparatus that the material in the pan sections continues to burn after the ignition device has been removed, and while the pan sections are still travelling around said annular-like suction box.

Means is provided for ejecting the sinter cakes from said pan sections at a point before they again reach said filling position.

Fig. 5 is a fragmentary enlarged vertical sectional view taken on the line 5-5 of'Fig. 2.

Fig. 6 is a fragmentary enlarged detailed view of a portion oi Fig. 1.

Fig. 7 is a fragmentary enlarged developed vertical sectional view taken on the line 7-7 of Fig. 6.

Fig. 8 is a fragmentary enlarged vertical sectional view taken onthe line 3-8 of Fig. 1.

Fig. 9 is a fragmentary enlarged sectional view of the. valve shown at the right hand end of The invention proposes anovel means for sealing the open top of said suction box in relation with said .fumace unit so that the air draft is forced to pass through the pan sections of the furnace unit.

The invention also contemplates a novel arrangement and operation of the means for ejecting the sintering cakes from the pan sections. The invention also proposes a novel arrangement and operation of the means for ignitin the material in each pan section forwards of the filling position of the pan sections. It is proposed to so arrange the igniting means that the Fig. 10'is a fragmentary enlarged vertical sectional view taken on the line lil'i0 of Fig. 1, illustrated with sintered material.

Fig. 11 is a fragmentary enlarged vertical sectional view of the central portion of the cylinder shown in Fig. 10, showing in particular the details of the small laterally projecting auxiliary cylinder.

Fig. 12 is a fragmentary enlarged longitudinal sectional view of the valve shown at the left side in Fig. 10.

The sintering apparatuain accordance with this invention, includesan annular-like wind or suction box ii for connection with a suction fan for providing the air draft needed in sintering. The fan connected with the box it is not disclosed on the drawings, since the arrangement ,sintered, as each pan section I! moves past 2.

point or area of said suction box [5. Thi filling means is characterized by a discharge hopper l8. The details of this hopper will not be given in this specification because supply hoppers for filling furnace pans and. other devices with granulated material is generally-known and forms no I part of this invention.

Immediately forwardly past the filling hopper [8, there is an ignition hood IQ for igniting the material in each .pan section II, as-each pan section passes this area of the suction box [5. Each 4 pan section I1 is intended to travel all around the annular-like suction box l5, and when they reach a point before the filling position characterized by the hopper l8 they encounter means for ejecting the sintered cakes. This means is characterized by an air ram 20.

The annular-like suction box IE is not 360 degrees in annular distance. There is a small open segment or section 2| as shown by the arrow on The suction box I5 has an open top. However, its

ends 24 are closed. Top flanges 25 extend outwards of the open section 2| from the tops of the ends 24 and are for the purpose of assisting in air sealing the suction box' I5. The annular unit It has a flat bottom 26 which rests upon and moves across the top flanges 25 and assists in air sealing the suction box 15. This is particularly true when the pan sections H are filled with sintering charges,'or with the sintered material.

The open top of the suction box I5 is also air sealed in relation to the entire bottom of the furnace unit l6. This is accomplished by sealing troughs 28 mounted around the suction box l5. These troughs 28 are arranged along the inside and outside diameters of the box l5. They extend 360 degrees, passing between the ends 24 of the suction box l5. Downwardly extending I Figure 2. For this reason we may describe the r 4 pintle 42, seeFigs. 2, 5 and 7. These pintles 42 project from the outside faces of the furnace units H. The outer ends of the pintles 42 are provided with radially extending levers 43 which have small outwardly extending projections 44 on their'outer ends. These projections 44 will strike. a complementary projection 45 on a stationary arm 46 mounted upon the side of the outer trough 28. The arm 46 is located at a position slightly past the left hand closed end 24 of the suctionbox l5, see Fig. 2. With this arrangement each grate 40 will be forced open when it reaches a position between the ends 24 of the suction box l5. to overcome the sticking tendency of the grates 40. The air ram 20 is located at a position in which the grates 40 are open. Immediately past this position, there is a track system 48 arranged to close the grates 40. Each grate is provided with several rollers 49 which will engage and ride the tracks 48 causing the grates 40 to close. These tracks 48 are arranged along the inner faces of the troughs 28. The top edge portions of the side walls of the suction box I5 are formed with inwardly directed flanges 50 which are provided with grooves 5| along which the rollers 49 move while the grates 40 are passing around the suction box I5. Small tongues 52, see Figs. 2 and 3 project from the bottom faces of the grates 4B in line with the rollers 49, and air seal the ends of the grooves 5| along the top flanges 25 at the ends 24.

flanges 29 are mounted upon the bottom portion of the furnace unit 16, along the inside and out side diameters thereof and extend into the sealing troughs 28. The sealing troughs 28 are filled I with a heavy sealing liquid or substance 30. For

example, a heavy grease. This grease forms a perfect air seal betweenthe suction box l5 and the furnace unit IS.

The annular furnace unit 16 is provided with several spokes 32 by which it is connected with an axial hub 33. This hub 33 is mounted upon vertical shaft 34 which is provided with a gear 35 engaged by a pinion 36 ofa speed reduction transmission 31 which is connected and driven by an electric motor 38. The transmission 31 is so designed that the furnace unit l6 makes one complete revolution for each period of time required to sinter the material in the pan sections ll. .At the present time a satisfactory period is The filling hopper I8 is stationarily supported by support arms 53 and 54. The arm 53 is connected with the outer side of the discharge hopper l8 and connects with the'side of one of the troughs 28. The inner arm 54 extends across the one side of the apparatus and is suitably supported by a support arm 55.

The ignition hood I9 is a standard ignition hood having the usual torches not illustrated on the drawing since they form no part of this invention. However the-ignition hood 1!! is supported and operated in a new way. The hood I9 is provided with side lugs 60 slidably engaging upon arms BI and 62. These arms are shaped to conform with the curvature of the suction box l5. The arms El and 62 form the bottom arms of two p-arallelograms of arms. 62 are horizontal but curved as shown in Figure 6. Each of these arms is supported by a pair of parallel upwardly and forwardly extending arms 64. The arms 64 are supported'on their top ends upon rods 65. These rods 65 are supported on their inner ends upon the support bar 54. At their outer ends, they are supported on brackets 66. The arrangement is such that when the ignition hood I9 is forced rcarwards it will also move upwards. The front and back edges of the ignition hood 19 are formed with flared portions 61. These flared portions 61 assist the ignition hood 19 in properly sitting upon the tops of the pan sections 11. The front flared portion 61 also acts as a. cam to force the ignition hood upwards, when the ignition hood is forced rearwards. A cylinder 68 provided with a piston rod 10 is used for this'purpose.

On each side of the ignition hood l9, there is a short rearwardly extending arm- 1 I. These arms II are pivotally mounted on their front ends on pintle rivets l2. Springs 13 are coaxially mounted on the pintle rivets 12 and act between the arms H and the hood IQ for normally urging the arms ll upwards into horizontal positions against top stop lugs 14 projecting from the sides of the This forcing is intended The arms BI and tion hood I9 while it is being moved rearwards,-

and then the tracks TI will discharge the ignition hood I9 upon the pan section I! which is to the back of the pan section IT upon which the hood I9 is illustrated on the drawings. The rear ends of the tracks TI have discharge portions I9 for this purpose.

The piston rod l8 connects with a piston 80 slidably mounted in the cylinder 88. The piston rod I8 is connected with the ignition hood I9 by a universal joint 8|. The front end of the cylinder 88 is supported by a universal joint 82 upon a support post 83. The piston 80 is controlled by an air valve 84. The air valve 84- has a control lever 85 which is connected with a rod 88 slidably mounted within the cylinder 68 and projecting from the front end of the cylinder. The rod 86 has a front downwardly extending projection 81 and a rear projection 88. The piston 8t engages against these projections 81 and 88 for alternat ing moving the rod 88 forwards and then rearwards and in this way controls said handle 85 of the valve 84 for operating the valve.

The valve M has a turnahle valve head 90 which in a forward'position of the handle 85 connects the air supply 95 with a pipe 92 which is connected with the front end of the cylinder 68. In this condition of the parts the air coming in from. the air supply pipe 9! will drive the piston 86 rearwards. When the piston 88 reaches its complete rear position it will, strike the projection 80, moving the rod 88, and so moving the handle 85 through 45 degrees. This will turn the valve head 90 45 degrees so that the air line 9| will be shut off, and the pipe 92 will be connected with a pipe 98 discharging into the atmosphere. Next the piston 80 is moved forwards. It will be moved forwards by the ignition hood I 9 which is riding upon one of the pan sections ll.

The air ram-20 is in the nature of a ram head 98 mounted upon a stem 99 which enters a vertical vylinder I 00. The stem 99 connects with a piston IN. A pipe I02 connects with the top of the cylinder .1 00. Another pipe I03 connects with the bottom of the cylinder I08. These pipes are connected up with an air valve I88. The air valve EM has a valve head I05 which may be turned by a handle I88. The handle 808 isurged rearwards by a spring I0l, so as to engage the handle ltd-against a stop lug I88. The handle- I88 is designed to move through 45 degrees. Each pan section I? has a projecting lug M0. These lugs H8 will ride against the handle I86 for turning the valve head i 85. As illustrated, the handle I88 is in its complete forward position. In this -position, the valve head 805 connects an air supply 89 with the pipe I82. The valve head I 85 also connects the pipe Hill with an air passage I II which. discharges into the atmosphere. In this condition of the parts, the incoming air from pipe use will drive the piston till downwards, and the ramming head 98 will enter the top of the pan section II striking the sinter cake in this section and breaking the sinter cake free from the pan section causing it to fall through the open bottom of the pan section.

The suitable conveyor, not illustrated on the operative position.

drawings, is intended to convey away the dis charged sinter cakes. When the lug II 0,passes the lever I08, the spring I 01 will move the lever I06 rearwards turning the-valve head I05 through 45 degrees. This causes the air pipe I09 to become connected with the pipe I03 and simultaneously' the air pipe I02 becomes connected with the atmosphere discharge passage I I I. The piston I0 I will therefore move upwards, lifting the ram head 98 to its raised position.

A safety bolt 6 is mounted on an intermediate point of the cylinder I00 and is for the purpose of preventing the ram head 98 from enteringone of the pan sections I'I when the pressure supply in the pipe line I09 fails, The bolt 8 is connected with a piston II1 which works in a small auxiliary cylinder IIO mounted on the side of the cylinder I00. A spring I I9 urges the piston Ill and the bolt H6 into an extended A small air tube I20 connects with the front of the cylinder H8 and with the supply pipe I09 so that the air pressure normally keeps the piston Ill and the bolt H6 retracted. This safety bolt III; will prevent the ram head 98 becoming jammed in one of the pan sections I1, in the event that the air pressure falls, and the furnace unit I6 continues turning.

An air shut-off plate I25 is mounted between the flanges 50 at an area beneath the ignition hood I9. The purpose ofthe plate I25 is to control the suction through the pan section H which is having its material ignited. The suction must not be too strong, or else it will interfere with the flames of the ignition torches.

The operation of the device is as follows:

The annular-like furnace unit I6 is slowly, but continuously being rotated indirectly by the electric motor 38. As the pan sections I1 pass beneath the filling position located by hopper I8, they will be filled with material to be sintered. The material in the pan section I I at the extreme right, in Fig. 2 is already ignited. The ignition hood I9 is now ready to move rearwards to engage upon the pan section I! which is second from the right in Fig. 2. At this instant the piston has engaged the projection 81 and has moved the rod 88 towards the right. This has turned the valve handle 85 to the position illustrated in Fig. 8. This has caused the valve head 80 to assume the position shown in Fig. 9. The air supply pipe Si is now connected with the pipe 92, and the piston 80 starts moving towards the left.

The piston rod l0 forces the ignition hood I9 rearwards. The flange 8! at the right cams up the ignition hood I9. The rollers 15 of the side arms II ride into the front portions 16 of the tracks I7 which lift the hood I9 completely upwards oif the pan section H. The piston rod 10 now moves the hood Ill rearwards until the rollers I5 fall from the ends I9 of the-tracks TI. The ignition hood is thus dropped on the pan section H which is second from the right as illustrated in Fig- 2. Since the furnace unit It is rotating clockwise, the pan section Il with the ignition hood I8 on "it, will move towards the right and the torches of the ignition ho'od I9 will ignite the material in the pan section, to be sintered. Of

' 7 downwards so that the rollers may pass. springs will return the arms H to their horizontal positions.

The, pan sections H which move past the ignition hood 15, continue to burn as theymove around the suction box i5. They will continue to burn for minutes, more orless depending merely upon the speed of operation of the machine. When they reach the position of the air ram 20 they will be discharged. At this position the lug i it of each pan section I! will engage the handle I06 of the valve I04 which controls the piston WI. The 'air ram- 98 will move smartly downwardly striking the sinter cake and knocking it from the pan section II. The grate 40 of the pan section I I will be opened at this mo.- merit. It was opened a short period before this time by the projection 44 of the lever 43 which connects with the pintle 42 of the grate 40, engaging the projection 45 of the arm 43. The

grate 40 will be closed by the tracks 48. The

emptied pan section I! is now ready to assume a position beneath the filling hopper I8 so as to be refilled. In this Way the cycle repeats.

While I have illustrated anddescribed the preferred embodiments of 'my invention, it is to be understood that I do not limit myself to the precise constructions herein disclosed and the right is reserved to all changes and modifications coming within the scope of the invention as defined in the appended claims.

Having thus described my invention, what I claim as new and desire to secure by United States I Letters Patent is:

1. In a rotary sintering apparatus having an annular-like suction box for connection with a suction fan for providing the air draft needed for sintering and an annular-like furnace unit rotative upon said suction box and having a plurality of radially disposed furnace pan sections, means for air sealing the open top of said suction box in relation with said furnace unit, comprising troughs fora sealing substance mounted about said suction box, and flanges mounted on said furnace unit and extending into said troughs.

2. In a rotary sintering apparatus having an annular-like suction box for connection with a suction fan for providing the air draft needed for sintering and an annular-like furnace unit rotative upon said suction box and having a plurality of radially disposed furnace pan sections, means for air sealing the open top of said suction box in relation with said furnace unit, comprising troughs for a sealing substance mounted about said suction box, andflanges mounted on said furnace unit and extending into said troughs, said troughs and flanges being mounted around the inner and outer diameters of said suction box and furnace unit.

3. In a rotary sintering apparatus having an annular-like open top suction box for connection with a suction fan for providing the air draft The needed for sintering and an annular-like furnace unit rotative upon said suction box, and means for air sealing the open top of said suction box in relation with said furnace unit including troughs for a sealing material mounted around one of said parts, and flange-like members on the otherof said parts and engaging into said troughs.

4. A sintering apparatus, comprising an annular-like suction box for connection with a suction fan for providing the air draft needed for sintering, an annular-like furnace unit rotative upon said suction boxand having a plurality of radially disposed furnace pan sections, means for filling said pan sections with material to be sintered as each pan section moves past one point of said suction box, means for igniting the material in each pan section immediately forwards of said filling position, and means for ejecting the sinter cakes from said pan sections at a point before they again reach said filling position, inincluding a. ram for ramming the sinter cakes from the pan sections.

5. A sintering apparatus, comprising an annular-like suction box of C-shape having an open top and closed ends and intended to be connected with a suction fan for providing the air draft needed for sintering material, an annular furnace unit rotative upon said suction box and having a plurality of radially disposed furnace pan sections provided with hingedly mounted bottom grates which may pivot downwards to open positions as they pass the ends of said suction box, means for filling said pan sections with material to be sintered as each pan section moves forwards over one end of said suction box, means for lgniting each pan section immediately forwards of said filling position, and means for ramming sinter cakes from said pan sections as each pan section is passing between the ends of said suction box.

6. A sintering apparatus, comprising an annular-like suction box of C-sh'ape having an open top and closed ends and intended to be connected with a suction fan for providingthe air draft needed for sintering material, an annular furnace unit rotative upon said suction box and having a plurality of radially disposed furnace pan sections provided with hingedly mounted bottom grates which may pivot downwards to open positions as they pass the ends of said suction box, means for filling said pan sections with material to be sintered as each pan section moves forwards over one end of said suction box, means for igniting each pan. section immediately forwards of said filling position, means for ramming sinter cakes from said pan sections, as each pan section is passing between the ends of said suction'box, and means for closing said grates between the ends of said suction box.

7. A sintering apparatus, comprising an an- .tions as they pass the ends of said suction box.

means for filling said pan sections with material to be sintered as each pan section moves forwards over one end of said suction box, means for igniting each pan section immediately forwards of said filling position, means for ramming sinter cakes from said pan sections, as each pan section is passing between the ends of said suction box,

and means for opening said grates as each pan section is passing between the ends of said suction box.

8. A sintering apparatus, comprising an annular-like suction box of C-shape having an open top and closed ends and intended to be connected with a suction fan for providing the air draft needed for sintering material, an annular furnace unit rotative upon said suction box'and having a plurality of radially disposed furnace pan sections provided with hingedly mounted bottom grates which may pivot downwards to open positions as they pass the ends of said suction box, means for filling said pan sections,with material to be sintered as each pansection moves forwards over one end of said suction box, means for igniting each pan section immediately forwards of said filling position, means for ramming sinter cakes from said pan sections, as each pan section .10 v v I section including an ignition hood, means for lowering andengaging said head upon one of the pan sections to travel along with the pan section is passing between the ends of said suction box,

- and means for opening said grates as each pan needed for sintering material, an annular furnace unit rotative upon said suction. box and having a plurality of radially disposed furnace pan sections provided with hingedly mounted bottom grates which may pivot downwards to open positions as they pass the ends of said suction box, means for filling said pan sections with material to be sintered as each pan section moves forwards over one end of said suction box, means for igniting each pan section immediately forwards of said filling position, means for ramming sinter cakes from said pan sections, as each pan section is passing between the ends of said suction box, means for opening said grates as each pan section is passing between the ends of said suction box, and means for closing said grates after their sinter cakes have been ejected.

10. A sintering apparatus, comprising an annular-like suction box of c-shape having an open top and closed ends and intended to be connected with a suction fan for providing the air draft needed for sintering material, an annular furnace unit rotative upon said suction box and" having a plurality of radially disposed furnace pan sections provided with hingedly mounted bottom grates which may pivot downwards to open positions as they pass the ends of said suction box, means for filling said pan sections with material to be sintered as each pan section moves forwards over'one end of said suction box, means for igniting each pan section immediately forwards of said filling position, means for ramming sinter cakes from said pan sections, as each pan section is passing between the ends of said s'uction box, means for opening said grates as each pan section is passing between the ends of said suction box, and means for closing said grates after their sinter cakes have been ejected including tracks for guiding the grates into closed positions.

11. A sintering apparatus, comprising an annular-like suction box of C-shape having an open top and closed end and intended to be connected with a suction fan for providing the air draft needed for sintering material, an annular furnace unit rotative upon said suction box and having a plurality of radially disposed furnace pan sections provided with hingedly mounted bottom grates which may pivot downwards to open positions as they pass the ends of said suction box, means for filling said pan sections with material to be sintered as each pen section moves forwards over one end of said suction box, means for igniting each pan section immediately forwards of said filling position, and means for ramming sinter cakes from said pan sections as each pan section is passing between the ends of said section box, said means for igniting each pan for a short distance, and means for raising andunit rotative upon said suction box and having a plurality'of radially disposed furnace pan sections provided with hingedly mounted bottom grates which may pivot downwardslto open positions as they pass the ends of said suction box, means for filling said pan sections with material to be sintered as each pan section moves forwards over one end of said suction box, means for igniting each pan section immediately forwards of said filling position, and means for ramming sinter cakes from said pan sections as each pan section is passing between the ends of said suction box, said means for igniting each pan section including an ignition head, means for lowering and engaging said head upon one of the pan sections to travel along with the pan section for a short distance, and means for raising and returning said ignition hood to its starting position so that it may engage on the next pan section, said ignition hood being slidably mounted upon the bottom arms of supporting parallelograms of arms.

13. A sintering apparatus, comprising anannular-like suction box of c-shape having an open top and closed ends and intended to be connected with a suction fan for providing the air draft .needed for sintering material, an annular furnace unit rotative upon said suction box and having a plurality of radially disposed furnace pan sections provided with hingedly mounted bottom grates which may pivot downward to open positions as they pass the ends of said suction box, means for filling said'pan sections with material to be sintered as each pan section moves forwards over one end of said suction box, means for igniting each pansection immediately forwards of said filling position, and means for ramming sinter cakes from said pan sections as each pan section is passing between the ends of said suction box, said igniting means including an ignition hood, means for slidably supporting said hood so that it may travel a short arcuate distance with said furnace unit, a track system for guiding said hood back to its starting position, arms mounted on said hood and having rollers engageable with said tracksystem, and piston means for moving said hood rearwards to engage with said track system and be moved back to its starting position.

14. A sintering apparatus, comprising an annular-like suction box of C-shape having an open top and closed ends and intended to be connected with a suction fan for providing the air draft needed for sintering material, an annular furnace unit rotative upon said suction box and having a' plurality of radially disposed furnace pan sections provided with hingedly mounted bottom grates which may pivot downwards to open positions as they pass the ends of said suction box, means for filling said pan sections with material to be sintered as each pan section moves forwards over one end of said suction box, means for igniting each pan section immediately forwards of said filling position, and means for ramming sinter cakes from said pan sections as each pan section .valve means for controlling said piston means.

15. A sintering apparatus, comprising an annular-like suction box of C-shape having an open top and closed ends and intended to be connected with a suction fan for providing the air draft needed for sintering material, an annular furnace unit rotative upon said suction box and having a plurality of radially disposed furnace pan sections provided with hingedly mounted bottom grates which may pivot downwards to open posi-' tions as they pass the ends of said suction box,

means for filling said pan sections with material to be sintered as each pan section moves forwards over one end of said suction box, means for igniting each pan section immediately forwards of said filling position, and means for ramming sinter cakes from said pan sections as each pan section a is passing between the ends of said suction box,

comprising an air ram, and an air valve for controlling said ram actuated with lugs projecting from said pan sections. 16. A sintering apparatus, comprising an annular-like 'suction box for connection with a suction fan for providing the air draft needed for sintering, an annular-like furnace unit rotative of said suction box, means for igniting the material in each pan section immediately forwards of said filling position, and means for ejecting the sinter cakes from said pan sections at a point before they'again reach said filling position, said igniting means including an ignition hood, and a plate stationarily mounted below said ignition hood and below said furnace unit for blocking off excesssive suction from the furnace pan section which is being ignited.

17. In a sintering apparatus, a suction box, a furnace unit having a plurality of furnace pan sections for material to be sintered and movably mounted on said suction box to move in a path along said suction box, means for moving said furnace unit in said path, and means for igniting the material in each of said pan sections at certain points along said path and including an ignition hood for engaging upon one of said pan sections at a starting point and then riding along with said pan section over said certain points, and means for returning said ignition hood to its startingpoint for engaging another one of said upon said suction box and having a plurality of radially disposed furnace pan sections, means for filling said pan sections with material to be sintered as each pan section moves past one point pan sections.

18. In a sintering apparatus, a suction box, a

furnace unit having a plurality of furnace pan sections for material to be sintered and movably mounted on said suction box to move in a path along said suction box, means for moving said furnace unit in said path, and means for igniting the material in each of said pan sections at certain points along said path and including an ignition hood, means forengaging and connecting said ignition hood upon one of said pan sections at a starting point for riding along with said pan section over said certain points, and means for disconnecting and returning said ignition hood to its starting position.

LOUIS GELBMAN. 

